A video decoding apparatus for reconstructing residual signals of a current block to be decoded by using a tree structure, includes: a decoder to decode, from a bitstream, prediction type information on the current block to be decoded, and divide, by the tree structure, the current block into one or more subblocks of which information on residual signals is to be reconstructed, by decoding, from the bitstream, a partition flag which indicates whether a block corresponding thereto is divided into blocks of a lower layer in the tree structure, wherein blocks which are not further divided are identified as the subblocks of which information on the residual signals is to be reconstructed; and a reconstructor to reconstruct information on residual signals of each of the subblocks from the bitstream.